| Your partner cannot force you to terminate the S Corporation. But, he can definitely withdraw as a partner. The timing consideration is not a relevant concern for the Tax Courts.
I suggest that you depart company and retain the S corporation as a 100% shareholder. There is no point to continue in the partnership with him considering his insistence that he wants to quit. It will not be a pleasant experience to continue to work for someone who does wish to appreciate your being a business relationship with him. | 
